Screen



June 16, 1925, 1,541,887

` H. F. WULLSTEIN SCREEN Filed Feb. l, 1924 3 Sheets-Sheet 2 lll.. 1

Euro1/04,1 o

Patented June 16, 1925.

UNITED STATES PATENT OFFICE. i

SCREEN.

.Application tiled February 1, 1924i. Serial No. 690,046.

To all whom t may concern:

Be it known that I, HERMAN F. l/VULLSTEIN, citizen of the United States, residing at Salt Lake City, in the county of Salt Lake and State of Utah, have invented certain new and useful Improvements in Screens; and I do declare the following to be a `full, clear, and exact description et the invention, such as will enable others skilled in the art to which it appertains to make and use the same. y

My invention relates to screens for ore, gravel, sand and numerous other materials and has reference more particularly to screens which are moved to cause proper feeding of the material therethrough.

@ne object is to provide self-acting means t'or quickly thrusting the screen upwardly when moved to an inoperative position and released, and a unique cam wheel arrangement for so moving and releasing the thrusting means at spaced intervals, while permitting said means to stand inert between such intervals.

Fach cam wheel is lormed with peripheral cam brought successively into play, and a :tui-ther aim is to provide novel operating means cooperable with said cams for intermittently turning the wheel.

Another object is to make novel provision for varying the 'intensity of the thrusts imparted to the screen.

Yet anotherA ob ect 1s to provide a screen thrusting means having unique construction and association with theinain frame of the machine.

A still further object iste provide screen thrusting means Ain two units, Ator spaced portions oil! the screen and to provide lior operating the cam Vwheels for these units alternately, or simultaneously, as desired.

.Another object is to make novel provision l for movably mounting the screen within theV main frame. 1 l

A still further aim is the provision oi a screening machine which will be compari tively simple and inexpensive,will have no working parts exposed to grit and dirt, and will be highly ciiicient and desirable.

lilith the foregoing in view, the invention resides in the novel subject matter hereinafter described and claimed, the description being supplemented by the accompanying drawings. v

Figure l is a top plan view of a vibrating screen constructed in accordance with my invention.

Figure 2 is a side elevation.

Figure 3 is an end elevation.

Figure 4 is a vertical longitudinal sectional view, as indicated by line 4-4 of Figure l. Y y

In the drawings above briefly described,

the numeral l designates anmain frame, and

while illustrated in horizontal position, is intended in most instances to be inclined to insure proper feeding of the material along the screening means. The frame l is provided with a pair of parallel side bars 2 whichare formed oi channel metal with their channels disposed inwardly. At one end the bars 2 are connected by a transverse bar 3a and landing plate 3 to receive the material being screened, while a transverse end bar 4 connects the other ends of said side bars. AIt desired, a relatively narrow .bar 5 .may also connect'the last mentioned ends ott the side bars 2 and may have its ends extended to provide handles or trunnions 6.

lDisposed longitudinally within the chan-A nels of the side bars 2 are two parallel screens supporting bars 7 which, in the present disclosure, are secured to transverse bars 8 whose ends project beyond the bars 7 through notches 9 in the lower edges of the bars 2, the projecting ends of said bars 8 being connected by longitudinal bars IO having central shoes 11 on their upper sides. The ends oi the bars 8 and consequently the bars l0 and 7, are supported by compression springs 12 seated within suitable saddles i3 which are secured to the bars'2 at the open lower ends of the notches 9, the strength ol said springsbeing adjustable by set screws or the like 14, f By means yet lo be described, the bars 10, 8 and 7 are intermittent-ly depressed against the .action ot the springs l2 and then released, causing saidsprings to quickly force the hars up wardly, thus forcibly thrusting upwardly on the screen supported by said bars. This screen may be of woven or other desired formation, but it may well be constructed of a plurality of spaced longitudinal .Fingers 15 extending from transverse carrying bars 16 whose ends extend into the channels of the side bars 2. These ends may in some instances be suitably guided for vertical movement and Ltree of connection with the bars 7, but in the present disclosure, the bars 1G may be considered as secured to said bars 7.

To limit the upward movement or the screen, I have shown a pair or angle metal bars 17 secured in the channels or the side bars 2 and provided with stop flanges in the upward paths ofthe bars 16. Guard plates 18 preferably contact iviththo inner edges or the top l'lz'ing'es of the bars 2 an'dwith the corresponding edges ot the bars 17, the lower portions ot said plates 18 having` ianges 19 resting' on the bars 17 to hold said plates against ,downward movement. Movement in other directions is prevented by bolts 20 which secure the plates to the bars 2. n

Cooperablel with the shoes 11 to alternately depress and release said shoes and associated parts to permit action or the springs 12, yare two cam wheels 21 having peripheral cams 22 or uniform circumferential length and uniform radial height, each cam being *preferablyy provided with an abrupt radially dispos'edrear end having a notch 23. Tivo proceeding and receding' operat-I ing yoles 24 straddle the upper portions or the cam wheels 21 respectively and are provided with pins 25 to successively engage the notchesv 23 and thus intermittently turn the wheels 21 a distance equiifalen't to the length of one cam 22.

In the preferred term o'lf construction, the yolfes 24k are carried by a pair or pitman rods 26 which are connected with cranks or eccentrics 27 on a transverse drive shaft 28 mounted in `suitable bearings 29, under the landing plate 3. At least one of the cranks or eccentrics 2'? is connected ivith the shaft 28 by a removable pin 30, so that its wrist pin may be either set in alignment with the wrist pin of the other crank or may be opposed thereto. Thus, the two cani wheels 21 may be operated either alternately, or simultaneously, as occasion may dictate. Dy alternate operation oit' the wheels, the screen vibrating means is caused to alternately torce opposite sides of the screen' upwardly against the stops` 1T, and the sereen is more gently vibrated than it' both sides are forced simultaneously upi'if'ard.

Attention may here be directed to the fact that when the springs 12 force upwardly on the screen and associated parts, the bars 16 strike the stops 17 before the shoes 11 can strike the' loiver' ends oit the cams 22; Thus, excessive wear on the shoes and cams is pre# vented. ily varying the space 31 which exiists between either shoe l1 and the low end Leanser ot any cam 22, when the bar 10 is raised. it will be seen that the distance which said shoe and associated parts will be depressed by the high end of the cam, ma,v be ericctively regulated and thus the intensityct the screen thrust may be varied as occasion may require.A To obtain proper relative adjustment of each cam Wheel 21 and shoe 11, I pref-er to mount said Wheel upon a carrying lever 32 fulcrumed at 33 to the adjacent side bar 2 and having an appropriate adlinstable connection 34 with said bar, to hold the lever in set position.

By lnoviding the vconstruction shown and described', a screen is produced which will b'e highly el'iicient and desirable. As excellent results are obtainable :trom the details disclosed, these details are by preference tollowed, but within the scope or the invention as claimed, nun'ierous changes may b'c made.

It may here be stated that while, in a sense, the screen is a vibrating screen, it not of the nature commonly known as a vibrating screen, in which the upward and downward impulses of the screen talle place in rapid succession and the material on said screen never nieves an appreciable distance from the latter. By my improved arrangement, in which the cam wheels are intermittently driven, a dilierentaction is obtained. lllach time one oi the cams 22 releases the cti-acting shoe 11, the' adjacent springs 12 come into play to forcibly thrust the screen upn'ardly, to the limit permitted by the stop bar 1T or its equivalent. This vmmfement ol the screen throws the' n'iaterial thereon high into the air and any particles of the material which would otherwise have a tendency to' clog the' screen are thus thro wn uiiii'ardly from it, so that clogging practically impossible. The material tails back on the screen while the latter stands inert, so that such material then si'tts through the screen. By the time all of the material thrown into' the air has again settled, the Cain wheel again functions, so that another forcible impulse willbe imparted upivardly on the screen. Thus, it will be seen (hat my invention distinguishes from the average vibrating screen, in that there is au appreciable lull. between the intervals at which the screen is forced upwardly, this lull beingl obtained by rotating the cam wheel or wheels yin a step-by-step manner, permitting said wheel or Wheels to ren'iiin absolutely inert for a proper period ol time' aitcr each turning thereof.

I claim:

1. A screening' device comprising a screen. 1

ihrustinmeans, and means l'or turning' length ot one cam at spaced intervals, perniitting it to remain inert between suchin tervals. j

2. A screening device comprising a screen, means `for thrusting said screen upwardly when said means is moved to a predetermined position and Vreleased, a rotatably mounted cam wheel having peripheral cams for so moving and releasing said screen thrusting means, and means co-operable with the cams of 'said wheel for turning the wheel a distance equivalentto the length of one cam at spaced intervals, permitting it to remain inert between such intervals.

A screening device comprisingascreen, means for thrusting said screen upwardly when said means is moved to a predetermined position and released, a rotatably mounted cam wheel having peripheral cam .tor so moving and releasing said screen thrusting means, and a proceeding and receding operating member for turning said cam wheel a distance equivalent to the length o Aof one cam at spaced intervals, permitting it to remain inert between such intervals.

A screening device comprising a screen, means for thrusting said screen upwardly when said means is movedto a predetermined position and released, a rotatably mounted cam wheel having peripheral cams 'l'or moving and releasing said screen thrusting means, and a proceeding and receding ope ating member co-operable with said cams :tor turning the wheel a distance equivalent to the length ot one cam at spaced intervals, permitting it to remain inert between 'such intervals.

ti. structure as specilied in claim 4l; said operating member having a yoke straddling a peripheral portion oit the cam wheel, said yokehaving a portion to engage the cams ot said wheel and turn 'the latter.

6. A screening device comprising screen thrusting means in two units for spaced parts ot a screen, each unit being operable when moved to an inoperative position and released, separate cam wheels ttor the two units having peripheral cams 'tor` moving said units to inoperative positions and then releasing them, and means operable tirst on one cam` wheelv and then on the other tor interniittently turning said wheels a disH tance equivalent to the angle between two :nfljacent cams.

7. A structure as specified in claim G; said intermittent turning means tor'said cam wheels being co-operable with the cams of said wheels. Y j

8. A structure as speciiied in claim 6; said intermittent turning means for said cam wheels comprising a pair of oppositely stroking proceeding and receding members cooperable with said cams.

9. A structure as specified in claim 1; to-

gether with means limiting the operative movement ot the screen thrusting means to a stroke ot less length than the radial height of thecams, and means for relatively adjusting said cam wheel and the cooperating part ofthe screen thrusting means toward and from each other.

10. A structure as specified in claim 1; together with means limiting the operative movement of the screen thrusting means to a stroke ot less length than the radial height of the cams, and an adjustable carrier for said cam wheel movable toward and from the portion of the screen thrusting means which cooperates with said wheel.

11. A device of the class described comprising a main trame having parallel side bars formed with downwardly opening notches, spring saddles secured to said bars .at the open ends of said notches, transverse screen shaking bars whose ends bass outwardly through said notches, springsin said saddles thrusting upwardly on said transverse bars, longitudinalbars secured to said transverse bars and located at the outer sides oit said side bars, and means tor alternately depressing and releasing said longitudinal bars.

12. A device ot the class described comprising a main frame having parallel side bars termed with downwardly opening notches, spring saddles secured to said bars at the open ends ot said notches, transverse screen shaking bars whose ends pass outwardly through said notches, springs in said saddles thrusting,upwardly on said trans- `verse bars, longitudinal bars securedto said transverse bars and located at thc outer sides ot said side bars, slices carried by said longi-k tudinal bars, and driven cam wheels cooperable with saidshoes for alternately depressing and releasing said longitudinal bars.

13. A device of the class described comprising a main trame having parallel side bars channeled at their inner sides, transverse screen carrying bars whose ends arc6 movably received in the side bar channels, and means tor vertically vibrating said. transverse bars.

lll. A device oi the-class described conn prising a main `,traine having parallel side bars channeled at their inner sides, longitudinal screen supporting bars in the side bar channels, projections extending out wardly from said screen supporting bars through openings in said side bars, andmeans associated with said projections for vertically vibratiner said screen supporting bars.

15. A device of the class described comprising a main trame having parallel side bars channeled at their inner sides, transverse screen carrying bars whose ends eX- tend movably into the side bar channels,

means for reri'ioaliy vibrating said transtacting with #he inner' edges of said stop verso bars, and stop Hangos in the side bar flanges, said guard plaies having Hangcs channels in the up 'ard paths o'fsaid transresting on said stop Hanges. 10

verse bars. In testimony whereof I have hereunto 16. A structure as specified in claim l5; a'ixed my signature.

together with guard plates scoured against the inner sides of said side bars and con- HERMAN F. VVULLSTEIN. 

